I get almost all my cat meds from Costco pharmacy at far better prices than I would pay at my vet; a few I get from KV Vet Supply, my vet faxes them the prescription. As with all meds, the more you buy, the less you pay - well, usually. That's because each time you refill you are paying a service charge as well as paying for the medication.

I had the radioactive iodine treatment done on one of my cats, and it worked out very well. Other, older cats have had the medication for years and all without ill affect. If your cat has a long life ahead of him, it can work out to be more cost effective to go with the iodine treatment.